Recent research discovered that sophisticated APT hackers group APT-C-36 targeting windows based platform to attackers Government institutes and corporate networks in Colombia.
Researchers believe that the threat actors are operating from South America using weaponized documents to targeting furthermore institutes such as the financial sector, petroleum industry, professional manufacturing, etc.
This APT group continuously targeting since April 2018 using spear-fishing email with a password protected RAR attachment to evade the security detection systems.
Researchers from 360 Threat Intelligence Center flagged almost 29 bait documents, 62 Trojan samples and multiple related malicious domains in total.
Most of the weaponized malicious documents are distributed via malspam emails with Attached MHTML macro based document.
The attachment contains the macro-enabled backdoor to gain a foothold into the target network to make it easier for later attacks.
According to 360 Threat Intelligence Center “Based upon victims’ backgrounds, the attacker is focusing on strategic-level intelligence and may also have motivations to steal business intelligence and intellectual property.”
Meanwhile, attackers masquerade as Colombian government websites also following spear-fishing emails, bait documents are used to compromising the corresponding victims.
Weaponized Malicious Docs
The attacker pretends to come from the National Directorate of Taxes and Customs:
Financial Institution (Banco Agrario)
- Information and Related Email of the Attacked Institution
The Banco Agrario is a Colombian state financial institution founded in 1999 to provide banking services in the rural sectors.
Spoofed Colombian National Cyber Police
The bait document was spoofed from the Colombian National Cyber Police (caivirtual.policia.gov.co):
Attackers mainly spoofing the original sources make it looks like legitimate for example by masquerading the National Civil Registry to attack the Institute for the Blind, mimics to be the Tax and CustomsAdministration to attack companies with international trade.
In Some cases, Attachment is encrypted and the decryption password left in the body of the mail which is one of the common way that used to avoid detection.
Apart from these attackers using VPN, Proxy to hide their IP address before sending the mail and the real IP will not be visible.
Once the Malicious files get executed then the copied file saved in
the %AppData% directory to save the encrypted log, network information, and system information and finally collected data will be uploaded into C2 server.